Marinellite Locality: Magliano Romano, Rome Province, Latium, Italy Blue crystalline Marinellite. Field of view 4 mm. Specimen and photo Leon Hupperichs. — Photo: Leon Hupperichs · CC BY-SA 3.0
Marinellite
Marinellite is an IMA-recognized mineral species in the silicate class, with the chemical formula Na₄₂Ca₆Al₃₆Si₃₆O₁₄₄(SO₄)₈Cl₂·6H₂O.
It crystallizes in the hexagonal crystal system (space group P31c). It is a member of the Cancrinite-sodalite structural group.
Key properties: Mohs hardness 5.5; specific gravity 2.405; White streak; Vitreous luster; optically uniaxial.
IMA symbol Mrn, IMA status: approved, named in 2002.
Found in a highly-reacted xenolith of evaporitic rock as volcanic ejecta.
It is found associated with Giuseppettite, sanidine, nepheline, haüyne, biotite, kalsilite.
The mineral was named to honor Giorgio Marinelli (1922-1993), Earth Science Department, University of Pisa, Italy.